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Full-Text Articles in Plant Pathology
Emergent Fungal Entomopathogen Does Not Alter Density Dependence In A Viral Competitor, Andrew M. Liebhold, Ruth Plymale, Joseph S. Elkinton, Ann E. Hajek
Emergent Fungal Entomopathogen Does Not Alter Density Dependence In A Viral Competitor, Andrew M. Liebhold, Ruth Plymale, Joseph S. Elkinton, Ann E. Hajek
Articles
Population cycles in forest Lepidoptera often result from recurring density-dependent epizootics of entomopathogens. While these systems are typically dominated by a single pathogen species, insects are often infected by multiple pathogens, yet little is known how pathogens interact to affect host dynamics. The apparent invasion of northeastern North America by the fungal entomopathogen Entomophaga maimaiga some time prior to 1989 provides a unique opportunity to evaluate such interactions. Prior to the arrival of E. maimaga, the oscillatory dynamics of host gypsy moth, Lymantria dispar, populations were apparently driven by epizootics of a nucleopolyhedrovirus. Subsequent to its emergence, E. …
Plant-Mediated Alteration Of The Peritrophic Matrix And Baculovirus Infection In Lepidopteran Larvae, Ruth C. Plymale, Michael J. Grove, Diana Cox-Foster, Nancy Ostiguy, Kelli Hoover
Plant-Mediated Alteration Of The Peritrophic Matrix And Baculovirus Infection In Lepidopteran Larvae, Ruth C. Plymale, Michael J. Grove, Diana Cox-Foster, Nancy Ostiguy, Kelli Hoover
Articles
The peritrophic matrix (PM) lines the midgut of most insects, providing protection to the midgut epithelial cells while permitting passage of nutrients and water. Herein, we provide evidence that plant-mediated alteration of the PM contributes to the well-documented inhibition of fatal infection by Autographa californica multiple nucleopolyhedrovirus (AcMNPV) of Heliothis virescens F. larvae fed cotton foliage. We examined the impact of the PM on pathogenesis using a viral construct expressing a reporter gene (AcMNPV-hsp70/ lacZ) orally inoculated into larvae with either intact PMs or PMs disrupted by Trichoplusia ni granulovirus occlusion bodies containing enhancin, known to degrade insect intestinal mucin. …
Induction Of Systemic Acquired Resistance In Cotton Foliage Does Not Adversely Affect The Performance Of An Entomopathogen, Ruth C. Plymale, Gary W. Felton, Kelli Hoover
Induction Of Systemic Acquired Resistance In Cotton Foliage Does Not Adversely Affect The Performance Of An Entomopathogen, Ruth C. Plymale, Gary W. Felton, Kelli Hoover
Articles
Baculoviral efficacy against lepidopteran larvae is substantially impacted by the host plant. Here, we characterized how baculoviral pathogenicity to cotton-fed Heliothis virescens larvae is affected by induction of systemic acquired resistance (SAR). Numerous studies have shown that SAR induced by the plant elicitor benzo-(1,2,3)-thiadiazole-7- carbothioic acid S-methyl ester (BTH) can protect against plant pathogens, but reports on the impacts of SAR on chewing herbivores or on natural enemies of herbivores are few. We found that BTH application significantly increased foliar peroxidase activity, condensed tannin levels, and total phenolic levels but did not alter dihydroxyphenolic levels. Consumption of BTH-treated foliage did …